%%
%% The LaTeX Companion, 3ed
%%
%% Example 9-4-3 on page I-679 in "The character scope of math alphabet identifiers".
%%
%% Copyright (C) 2022 Frank Mittelbach
%%
%% It may be distributed and/or modified under the conditions
%% of the LaTeX Project Public License, either version 1.3c
%% of this license or (at your option) any later version.
%%
%% See https://www.latex-project.org/lppl.txt for details.
%%

\documentclass{tlc3exa}
\pagestyle{empty}
\setcounter{page}{6}
\setlength\textwidth{159.0pt}

  % use lualatex

%StartShownPreambleCommands
\usepackage{fontspec}
\setmainfont{Alegreya}
\setsansfont{Alegreya Sans}
%StopShownPreambleCommands

\begin{document}
$            0123\ lower\ UPPER\ \Delta\Gamma $ \par
$    \mathbf{0123\ lower\ UPPER\ \Delta\Gamma}$ \par
$    \mathsf{0123\ lower\ UPPER\ \Delta\Gamma}$ \par
$\mathnormal{0123\ lower\ UPPER\ \Delta\Gamma}$
\end{document}
